Trapped sperm

• This can occur if the tubes become blocked due to infection or injury.
• Another reason for trapped sperm is a condition called congenital bilateral absence of the vas deferens, where the two vas deferens tubes are missing at birth. Because men with this condition often also lack seminal vesicles, one possible sign of this condition is a low semen volume.
• In a vasectomy the vas deferens are deliberately cut to keep sperm in the testicles.